scholarly journals First Report of Tomato Mottle Geminivirus Infecting Tomatoes in Yucatan, Mexico

Plant Disease ◽  
1998 ◽  
Vol 82 (5) ◽  
pp. 592-592 ◽  
Author(s):  
E. R. Garrido-Ramirez ◽  
R. L. Gilbertson
Keyword(s):  
Mixed Infection ◽  
Blot Hybridization ◽  
Tomato Leaf ◽  
Western Hemisphere ◽  
Leaf Sample ◽  
Degenerate Primers ◽  
Tomato Production ◽  
Tomato Plants ◽  
First Report ◽  
Stunted Growth

Whitefly-transmitted geminiviruses are a major constraint on tomato production in Mexico (3). In the Yucatan State, these viruses can cause serious losses in late season plantings. As part of an effort to characterize these viruses, leaf samples from four tomato plants showing symptoms of geminivirus infection, such as stunted growth and leaf mottling and deformation, were collected from a single field in the Yucatan State in February, 1996. Geminivirus nucleic acids were detected in leaf samples from all four plants by squash blot hybridization analysis with a general DNA probe for Western Hemisphere whitefly-transmitted geminiviruses (2). Nicotiana benthamiana plants inoculated with sap prepared with leaf tissue from one plant developed stunted growth and leaf mottling and deformation. When graft-transmitted from N. benthamiana to tomato, the geminivirus(es) induced leaf mottling and deformation, which were similar to symptoms in the field-collected tomato plants. The presence of geminivirus DNA in the sap- and graft-inoculated plants was confirmed with the polymerase chain reaction (PCR) and degenerate primers for the DNA-A (PAL1v1978 and PAR1c496) or DNA-B (PBL1v2040 and PCRc1) components of whitefly-transmitted geminiviruses (4). Using PCR and these degenerate primers, approximately 1.1-kb DNA-A and approximately 0.6-kb DNA-B fragments were amplified from DNA extracts prepared from leaves of each of the four Yucatan tomato plants. No DNA fragments were amplified from these extracts with primers for pepper huasteco geminivirus (pAL1c2329 and pAL1v1471, or pBR1c840 and pBL1v1830). To determine the identity of the geminivirus(es) infecting these tomato plants, the PCR-amplified DNA-A and DNA-B fragments from one of the samples were cloned and sequenced. Comparisons made with these sequences revealed two distinct types of DNA-A and DNA-B clones, indicating a mixed infection of at least two bipartite geminiviruses. DNA-A and DNA-B sequences of one set of clones were >97% identical to sequences of tomato mottle geminivirus (ToMoV) from Florida (1). The presence of ToMoV in all four tomato leaf samples was demonstrated by the PCR-mediated amplification of a 0.9-kb DNA-A fragment with ToMoV-specific primers (pAL1v2295 and pAR1c580). The identity of this 0.9-kb DNA fragment was further confirmed based upon its hybridization with a full-length clone of ToMoV DNA-A under high stringency conditions (2). A data base search made with the sequence of the other type of DNA-A clone revealed sequence identities of <70% with various bipartite geminiviruses (e.g., identities of 70% with tomato mottle, 69% with Sida golden mosaic, 67% with bean dwarf mosaic, and 66% with taino tomato mottle and with potato yellow mosaic), which confirmed that a second geminivirus was present in a mixed infection with ToMoV in this tomato leaf sample. To confirm the bipartite nature of this geminivirus, a DNA-B fragment that contained the common region (CR) sequence was amplified from the same sample with PCR and primers PBL1v2040 and PBR1c970 (a degenerate primer that anneals within the BV1 open reading frame; F. M. Zerbini and R. L. Gil-bertson, unpublished data), cloned, and sequenced. The CR sequence of this DNA-B fragment was 96% identical to that of the DNA-A fragment, which establishes the presence of another bipartite geminivirus in this sample. This is the first report of ToMoV in Mexico. These results also suggest that at least two bipartite geminiviruses may infect tomatoes in the Yucatan Peninsula. References: (1) A. M. Abouzid et al. J. Gen. Virol. 73:3225, 1992. (2) R. L. Gilbertson et al. Plant Dis. 75:336, 1991. (3) J. E. Polston and P. K. Anderson. Plant Dis. 81:1358, 1997. (4) M. R. Rojas et al. Plant Dis. 77:340, 1993.

scholarly journals First Report of Mosaic Disease Caused by Colombian datura virus on Solanum lycopersicum Plants Commercially Cultivated in Japan

Plant Disease ◽  
2014 ◽  
Vol 98 (5) ◽  
pp. 698-698 ◽  
Author(s):  
Y. Tomitaka ◽  
T. Usugi ◽  
R. Kozuka ◽  
S. Tsuda
Keyword(s):  
Nucleotide Sequence ◽  
Solanum Lycopersicum ◽  
Mosaic Disease ◽  
Causal Agent ◽  
Cultivated Plants ◽  
Rt Pcr ◽  
Degenerate Primers ◽  
Specific Primers ◽  
Tomato Plants ◽  
First Report

In 2009, some commercially grown tomato (Solanum lycopersicum) plants in Chiba Prefecture, Japan, exhibited mosaic symptoms. Ten plants from a total of about 72,000 cultivated plants in the greenhouses showed such symptoms. To identify the causal agent, sap from leaves of the diseased plants was inoculated into Chenopodium quinoa and Nicotiana benthamiana plants. Local necrotic lesions appeared on inoculated leaves of C. quinoa, but no systemic infection was observed. Systemic mosaic symptoms were observed on the N. benthamiana plants inoculated. Single local lesion isolation was performed three times using C. quinoa to obtain a reference isolate for further characterization. N. benthamiana was used for propagation of the isolate. Sap from infected leaves of N. benthamiana was mechanically inoculated into three individual S. lycopersicum cv. Momotaro. Symptoms appearing on inoculated tomatoes were indistinguishable from those of diseased tomato plants found initially in the greenhouse. Flexuous, filamentous particles, ~750 nm long, were observed by electron microscopy in the sap of the tomato plants inoculated with the isolate, indicating that the infecting virus may belong to the family Potyviridae. To determine genomic sequence of the virus, RT-PCR was performed. Total RNA was extracted from the tomato leaves experimentally infected with the isolate using an RNeasy Plant Mini kit (QIAGEN, Hilden, Germany). RT-PCR was performed by using a set of universal, degenerate primers for Potyviruses as previously reported (2). Amplicons (~1,500 bp) generated by RT-PCR were extracted from the gels using the QIAquick Gel Extraction kit (QIAGEN) and cloned into pCR-BluntII TOPO (Invitrogen, San Diego, CA). DNA sequences of three individual clones were determined using a combination of plasmid and virus-specific primers, showing that identity among three clones was 99.8%. A consensus nucleotide sequence of the isolate was deposited in GenBank (AB823816). BLASTn analysis of the nucleotide sequence determined showed 99% identity with a partial sequence in the NIb/coat protein (CP) region of Colombian datura virus (CDV) tobacco isolate (JQ801448). Comparison of the amino acid sequence predicted for the CP with previously reported sequences for CDV (AY621656, AJ237923, EU571230, AM113759, AM113754, and AM113761) showed 97 to 100% identity range. Subsequently, CDV infection in both the original and experimentally inoculated plants was confirmed by RT-PCR using CDV-specific primers (CDVv and CDVvc; [1]), and, hence, the causal agent of the tomato disease observed in greenhouse tomatoes was proved to be CDV. The first case of CDV on tomato was reported in Netherlands (3), indicating that CDV was transmitted by aphids from CDV-infected Brugmansia plants cultivated in the same greenhouse. We carefully investigated whether Brugmansia plants naturally grew around the greenhouses, but we could not find them inside or in proximity to the greenhouses. Therefore, sources of CDV inoculum in Japan are still unclear. This is the first report of a mosaic disease caused by CDV on commercially cultivated S. lycopersicum in Japan. References: (1) D. O. Chellemi et al. Plant Dis. 95:755, 2011. (2) J. Chen et al. Arch. Virol. 146:757, 2001. (3) J. Th. J. Verhoeven et al. Eur. J. Plant. Pathol. 102:895, 1996.

scholarly journals Yellow Net of Triumffeta Is Caused by a Geminivirus: A First Report

Plant Disease ◽  
1998 ◽  
Vol 82 (1) ◽  
pp. 127-127 ◽  
Author(s):  
Vipin Hallan ◽  
Sangeeta Saxena ◽  
B. P. Singh
Keyword(s):  
Rainy Season ◽  
Blot Hybridization ◽  
Southern Blot Hybridization ◽  
Viral Disease ◽  
Hybridization Experiment ◽  
Dorsal Side ◽  
Causal Agent ◽  
Degenerate Primers ◽  
First Report ◽  
Initial Symptoms

Triumffeta rhomboidiaceae Jacq. (Tiliaceae family) is an annual rainy season weed that is commonly found throughout India. For the last 3 years, during the rainy season, several plants of T. rhomboidiaceae in and around the gardens of the National Botanical Research Institute have been found with vein yellowing symptoms. The initial symptoms were vein clearing but in later stages the veins became yellow and thickened. In severe cases, the chlorosis extends into interveinal areas, resulting in complete yellowing of the leaves. In a few cases, green leafy or thorny enations could be seen on the dorsal side of the leaf. The disease was investigated to identify the causal agent. Vector transmission studies showed that the causal agent is transmitted by the whitefly, Bemisia tabaci, from infected to healthy seedlings of T. rhomdoidiaceae. Since whitefly transmission of the disease is consistent with a geminivirus as the causal agent, the role of such a virus was investigated. DNA isolated from Triumffeta plants (both from the infected plants in the field as well as from those inoculated experimentally in the greenhouse) showing above mentioned symptoms was amplified with two sets of degenerate primers, PAL1v1978/PAR1c496 (set 1) and PAL1v1978/PCRc1 (set 2), that have been shown to be specific for DNA-A of whitefly transmitted geminiviruses (WTGs), in polymerase chain reaction (1). We could amplify DNA-A fragments of approximately 1.2 kb from set 1 and 0.7 kb from set 2, as expected (1). DNA isolated from healthy seedlings gave no amplification of such fragments. Identification of the amplified DNA fragments (from infected samples) to be of geminiviral in nature was confirmed by Southern blot hybridization carried out under high stringency conditions. DNA-A of Indian tomato leaf curl virus (2) was used as a general probe for WTGs for the above hybridization experiment. Therefore, Triumffeta yellow net disease is caused by a geminivirus. A review of literature revealed that there is no record of a viral disease affecting this weed and, therefore, this is the first report of a viral disease affecting this plant. References: (1) M. R. Rojas et al. Plant Dis. 77:340, 1993. (2) K. M. Srivastava et al. J. Virol. Methods 51:297, 1995.

scholarly journals A New Tomato leaf curl virus from Mayotte

Plant Disease ◽  
2004 ◽  
Vol 88 (6) ◽  
pp. 681-681 ◽  
Author(s):  
J. M. Lett ◽  
H. Delatte ◽  
F. Naze ◽  
B. Reynaud ◽  
A. L. Abdoul-Karime ◽  
...  
Keyword(s):  
Tomato Leaf ◽  
Nucleotide Identity ◽  
Degenerate Primers ◽  
Sequence Alignments ◽  
Tomato Plants ◽  
Embl Accession ◽  
Pcr Products ◽  
Tomato Leaf Curl ◽  
Leaf Curl Virus ◽  
Leaf Curl

In June 2003, symptoms of stunting and leaf curling resembling symptoms of tomato leaf curl disease, as well as reductions in yields, were observed on tomato plants in the western (Combani and Kahani) and eastern (Dembeni, Kaoueni, and Tsararano) regions of Mayotte, a French island in the Comoros Archipelago located in the northern part of the Mozambique Channel. The whitefly, Bemisia tabaci (Gennadius), was observed colonizing tomato plants and other vegetable crops at low levels. Overall, 13 leaf samples with symptoms were collected from tomato plants among the five regions and tested for the presence of begomoviruses using a polymerase chain reaction (PCR) assay with two sets of degenerate primers designed to amplify two regions of the A component of begomoviruses. Primers MP16 and MP82 amplify an approximately 500-bp fragment located between the intergenic conserved nonanucleotide sequence and the first 200 bp of the coat protein (CP) gene (2). Primers AV494 and AC1048 amplify the approximately 550-bp core region of the CP gene (3). Six leaf samples, one from Combani, three from Dembeni, and two from Kahani, gave a PCR product of the expected size with both sets of primers. No PCR products were obtained with degenerate primers designed for begomovirus DNA B or β. The approximately 500- and 550-bp PCR products from one sample each of Combani (EMBL Accession Nos. AJ620912 and AJ620915, respectively), Dembeni (EMBL Accession Nos. AJ620911 and AJ620914, respectively), and Kahani (EMBL Accession Nos. AJ620913 and AJ620916, respectively) were sequenced. For the 489-bp sequences obtained with the MP16/MP82 primer set, the three isolates had 90 to 95% nucleotide identity (DNAMAN; Lynnon BioSoft, Quebec). The most significant sequence alignments (NCBI and BLAST) were with begomoviruses; 80 to 83% nucleotide identity was obtained with the Tomato yellow leaf curl Morondava virus (TYLCMV) isolates from Madagascar (EMBL Accession Nos. AJ422123 and AJ422124), 80 to 82% nucleotide identity was obtained with the South African cassava mosaic virus (SACMV) isolates (GenBank and EMBL Accession Nos. AF155806 and AJ422132), and 79 to 81% nucleotide identity was obtained with the East African cassava mosaic Malawi virus (EMBL Accession No. AJ006460). For the 522-bp sequences obtained with the AV494/AC1048 primer set, 95 to 97% nucleotide identity was shown between the three isolates. The most significant sequence alignments were also with begomoviruses; TYLCMV isolate Morondava (EMBL Accession No. AJ422125) with 86 to 88% nucleotide identity, Tomato yellow leaf curl virus isolates (GenBank and EMBL Accession Nos. AF105975, AJ489258, AB014346, AF024715, AF071228, and X76319) with 86 to 87% nucleotide identity, and SACMV isolate M12 (EMBL Accession No. AJ422132) with 85 to 86% nucleotide identity. According to the current taxonomic criteria for the provisional classification of a new begomovirus species, nucleotide sequence identity in the core region of the CP <90% (1), the tomato begomovirus from Mayotte is a new species and is provisionally named Tomato leaf curl Mayotte virus. References: (1) J. K. Brown et al. Arch. Virol. 146:1581, 2001. (2) P. Umaharan et al. Phytopathology 88:1262, 1998. (3) S. D. Wyatt and J. K. Brown. Phytopathology 86:1288, 1996.

scholarly journals First Report of Tomato yellow leaf curl virus on Tomato Crops in Greece

Plant Disease ◽  
2001 ◽  
Vol 85 (6) ◽  
pp. 678-678 ◽  
Author(s):  
A. D. Avgelis ◽  
N. Roditakis ◽  
C. I. Dovas ◽  
N. I. Katis ◽  
C. Varveri ◽  
...  
Keyword(s):  
Disease Incidence ◽  
Rflp Analysis ◽  
Tomato Yellow Leaf ◽  
Yellow Leaf ◽  
Degenerate Primers ◽  
Sequence Comparisons ◽  
Tomato Plants ◽  
First Report ◽  
Leaf Curl Virus ◽  
Leaf Curl

In late summer 2000, tomato (Lycopersicon esculentum Mill.) grown in greenhouses in Ierapetra, Tympaki, and Chania (Crete) showed leaf curling, reduced leaf size, yellowing, shortened internodes, and a bushy appearance. More than 30 ha of tomato greenhouses were affected and the disease incidence ranged from 15 to 60% with estimated crop losses of over $500,000. Similar symptoms were observed in tomato samples from Marathon (Attiki) and Southern Peloponnese. All greenhouses with infected plants were infested with high populations of Bemisia tabaci (Gennadius), which were also observed outside the greenhouses on several weeds. Tomato symptoms were similar to those caused by Tomato yellow leaf curl virus (TYLCV). The assumed virus could not be transmitted mechanically but successful transmission was obtained by grafting onto healthy tomato plants. Over 100 samples of symptomatic tomato plants collected from Crete and southern Peloponnese gave positive reactions when tested by ELISA using monoclonal antibodies to TYLCV-European (Adgen Ltd). The serological results were confirmed by PCR using two pairs of primers, universal degenerate (1) and MA 13 and MA 17 (2), amplifying different parts of the virus genome. The restriction fragment length polymorphism (RFLP) analysis (AluI, HaeIII, and TaqI) of the 541 bp amplicon obtained with the degenerate primers showed patterns similar to TYLCV-Is (Israeli species). The second pair of primers gave the expected 348 bp product, which was sequenced. Sequence comparisons revealed 99% identity with TYLCV-Is (EMBL no. X15656, X76319). The resulting sequence was at least 97.7% identical to sequences of TYLCV isolates from the Dominician Republic (EMBL no. AF024715), Cuba (EMBL no. AJ223505), Portugal (EMBL no. AF105975), Iran (EMBL no. AJ13271), and Spain (EMBL no. AF071228). The disease appeared for the first time in 1992 in Tymbaki, but was limited to very few plants in one glasshouse. However, the cause was not determined. To our knowledge, this is the first report of TYLCV of the Begomovirus genus in Greece. References: (1) D. Deng et al. Ann. Appl. Biol. 125:327, 1994. (2) J. Navas-Castillo et al. J. Virol. Methods 75:195, 1998.

scholarly journals Geminiviruses Infecting Tomato Crops in Nicaragua

Plant Disease ◽  
2000 ◽  
Vol 84 (8) ◽  
pp. 843-846 ◽  
Author(s):  
Aldo Rojas ◽  
Anders Kvarnheden ◽  
Jari P. T. Valkonen
Keyword(s):  
Phylogenetic Analysis ◽  
Tomato Leaf ◽  
The Other ◽  
Central American ◽  
Mottle Virus ◽  
Degenerate Primers ◽  
Tomato Plants ◽  
Polymerase Chain ◽  
Tomato Leaf Curl ◽  
Leaf Curl Virus

Geminiviruses transmitted by whiteflies are believed to be responsible for the devastating epidemic in tomato crops in Nicaragua, as well as in other Central American countries. Polymerase chain reaction with degenerate primers was used to amplify partial sequences of the geminivirus coat protein gene from samples of diseased tomato plants collected from the major tomato-growing areas of Nicaragua. The data indicated the presence of geminiviruses in all tested regions of the country. DNA sequence analysis and phylogenetic analysis of the amplified sequences showed that they corresponded to four different geminiviruses related to the other begomoviruses native to the Americas. One of the viruses, which was detected in three regions of Nicaragua, is probably Sinaloa tomato leaf curl virus. The sequences of two of the other detected viruses showed close relationships with several geminiviruses, including Tomato mottle virus, Tomato leaf crumple virus, and Sida golden mosaic virus, all of which previously have been reported from Central America. The fourth virus is closely related at sequence level to a tomato-infecting geminivirus from Honduras, putatively designated Tomato mild mottle virus. This virus seems to be different from the other known American begomoviruses because it groups separately in the phylogenetic analysis.

scholarly journals Detection of Satellite DNA Beta in Tomato Plants with Tomato Yellow Leaf Curl Disease in Jordan

Plant Disease ◽  
2014 ◽  
Vol 98 (7) ◽  
pp. 1017-1017 ◽  
Author(s):  
G. Anfoka ◽  
F. Haj Ahmad ◽  
M. Altaleb ◽  
M. Al Shhab
Keyword(s):  
Mixed Infection ◽  
Tomato Yellow Leaf ◽  
Single Infection ◽  
Yellow Leaf ◽  
Tomato Production ◽  
Tomato Plants ◽  
Pcr Products ◽  
Leaf Curl Virus ◽  
Leaf Curl Disease ◽  
Leaf Curl

In Jordan, as well as many countries in the region, tomato production is threatened by begomoviruses belonging to the tomato yellow leaf curl virus complex (1). In 2013, an experiment was conducted at Homret Al-Sahen, Jordan (GPS coordinates 32°05′06″ N, 35°38′52″ E), to evaluate different tomato breeding lines for resistance against viruses causing tomato yellow leaf curl disease (TYLCD). Disease symptoms, typical of those caused by TYLCV complex, were observed in many susceptible lines. However, some lines exhibited unusual symptoms including severe leaf curling and stunting. To identify the causal agent of these symptoms, total nucleic acids were extracted from 21 symptomatic plants and used as templates in PCR analysis using nine primers, previously described to detect Tomato yellow leaf curl virus, Tomato yellow leaf curl Sardinia virus, and two recombinants between TYLCV and TYLCSV (3). In addition, the universal primer pair β01/β02 (2) was used to investigate the association of satDNA β with the disease. The PCR products characteristic of TYLCV (664 bp) could be amplified from five plants indicating single infection, while double infection with TYLCV and satDNA β (1,320 bp) was detected in seven plants. Mixed infection with TYLCV, TYLCSV (628 bp), and satDNA β was detected in another seven symptomatic plants and only one plant was infected with TYLCV and TYLCSV. A single plant had mixed infection with TYLCV, TYLCSV, and RecA (a recombinant between TYLCV/TYLCSV) (538 bp) (3). Amplicons obtained from two plants using β01/β02 primers were directly sequenced as 1,320-bp PCR products. Both sequences were found identical and, therefore, this sequence was deposited in the GenBank under the accession number KJ396939. Phylogenetic analysis revealed that this satDNA β sequence had the highest nucleotide (95%) identity with Okra leaf curl virus (OkLCV) satDNA 3 (AF397217) and OkLCV satDNA 10 (AF397215). The contribution of the satDNA β in the modulation of the TYLCD symptoms will be further investigated. Few years ago, another satDNA (Tomβ01-Om) was reported in Oman to be associated with TYLCD (4). However, to the best of our knowledge, this is the first report on the detection of satDNA β in tomato plants infected with viruses causing TYLCD in Jordan. The increasing diversity of begomoviruses causing TYLCD in the region is of great concern due to the possible emergence of more virulent viruses and subsequent increased losses to tomato production. References: (1) G. Anfoka et al. J. Plant Pathol. 90:311, 2008. (2) R. W. Briddon and J. Stanley. Virology 344:198, 2006. (3) S. Davino et al. Virus Res. 143:15, 2009. (4) A. J. Khan et al. Virus Gene 36:169, 2008.

scholarly journals First Report of Turnip mosaic virus in Tomatillo (Physalis philadelphica) in California

Plant Disease ◽  
2012 ◽  
Vol 96 (2) ◽  
pp. 296-296 ◽  
Author(s):  
H.-Y. Liu ◽  
S. T. Koike ◽  
D. Xu ◽  
R. Li
Keyword(s):  
Mosaic Virus ◽  
Green Peach Aphid ◽  
Chenopodium Quinoa ◽  
Turnip Mosaic Virus ◽  
Causal Agent ◽  
Western Hemisphere ◽  
Degenerate Primers ◽  
First Report ◽  
Severe Stunting ◽  
Access Period

Tomatillo is an important vegetable in Mexican cuisine. It is of Mesoamerica origin and now is grown widely in the Western Hemisphere. In 2011, 2% of commercially grown tomatillo plants in San Benito County, California exhibited severe stunting with foliage showing mosaic symptoms and leaf distortion. The fruits on infected plants were mottled and unmarketable. Flexuous filamentous-shaped virus particles of 800 to 850 nm long and 11 to 12 nm wide were observed from sap of the symptomatic plants with a transmission electron microscope. Sap from the diseased tomatillo plants reacted positively in an immunostrip assay for potyvirus (Agdia Inc., Elkhart, IN), indicating a potyvirus was associated with the disease. The causal agent was mechanically transmitted from the diseased field plants to six virus-free greenhouse tomatillo plants and all inoculated plants induced identical symptoms. The causal agent was also transmitted to Chenopodium quinoa and C. murale (chlorotic local lesions) and Nicotiana clevelandii, N. tabacum, and Physalis wrightii (systemic symptoms). The disease was also transmitted to tomatillo plants by the green peach aphid (Myzus persicae) in a nonpersistent manner (1-min acquisition access period and 1-min transmission access period with no latent period). To further identify the causal agent, total nucleic acids were extracted by a cetyltrimethylammoniumbromide (CTAB) method (2) and tested by reverse transcription-PCR using potyvirus degenerate primers CIFor and CIRev (1). An amplicon of approximately 700 bp from the diseased tomatillo was cloned and sequenced. Analysis of the 631-bp partial CI sequence (GenBank Accession No. JN601884) showed that the virus had 93.6% nucleotide identity and 100% amino acid identity with cognate regions of Turnip mosaic virus (TuMV) (GenBank Accession No. D10927). Our results indicated that the disease was caused by TuMV. To our knowledge, this is the first report of TuMV in tomatillo. Since TuMV has a wide host range and is readily transmitted by green peach aphids, TuMV could be a new threat to tomatillo production in California. References: (1) C. Ha et al. Arch. Virol. 153:25, 2008. (2) R. Li et al. J. Virol. Methods 154:48, 2008.

scholarly journals Partial Characterization of Two Whitefly-Transmitted Geminiviruses Infecting Tomatoes in Venezuela

Plant Disease ◽  
1997 ◽  
Vol 81 (3) ◽  
pp. 312-312 ◽  
Author(s):  
P. Guzman ◽  
C. R. Arredondo ◽  
D. Emmatty ◽  
R. J. Portillo ◽  
R. L. Gilbertson
Keyword(s):  
Blot Hybridization ◽  
Western Hemisphere ◽  
Hybridization Analysis ◽  
Yellow Mosaic Virus ◽  
Alternate Host ◽  
Degenerate Primers ◽  
Significant Yield ◽  
Relationship Of ◽  
Leaf Curl Virus

Whitefly-transmitted geminiviruses can cause significant yield losses on tomatoes (Lycopersicon esculentum Mill.) in Venezuela. To identify the geminivirus(es) infecting tomatoes in Venezuela, 20 tomato samples from commercial tomato fields in four states and one weed (Euphorbia heterophylla L.) sample were examined for geminivirus infection. All samples showed symptoms generally associated with geminivirus infection, including golden or yellow mosaic, mottling, crumpling and/or distortion of leaves, and, in some cases, stunted and distorted growth. Through the use of squash blot hybridization analysis and a general probe for Western Hemisphere whitefly-transmitted geminiviruses (4), geminivirus nucleic acids were detected in 19 of 20 tomato samples and the weed sample. No samples were infected with tomato yellow leaf curl virus (TYLCV), based on squash blot hybridization analysis with a TYLCV-specific probe. With polymerase chain reaction (PCR) and degenerate primers for whitefly-transmitted geminiviruses (PAL1v1978 and PAR1c496) (4), an approximately 1.2-kb DNA-A fragment was amplified from the 19 squash blot-positive tomato samples and from the weed sample. No DNA fragment was amplified from any samples when TYLCV-specific primers (PTYC1v2406 and PTYIRc287) (3) were used. PCR-amplified DNA-A fragments from four samples representing four different states [Monagas (5L), Guarico (3M), Aragua (3R), and Portuguesa (2U)] were cloned and sequenced. Partial AC1, AV1, and complete common region (CR) sequences of the 5L, 3M, and 2U DNA-A fragments were 92 to 93, 93, and 95 to 97% identical, respectively, indicating that these were DNA-A clones of the same virus. Furthermore, these sequences were 91 to 92, 92 to 95, and 93 to 95% identical, respectively, to sequences of homologous regions of potato yellow mosaic virus (PYMV), indicating that these tomato-infecting geminiviruses are isolates or strains of PYMV. The partial AC1, AV1, and complete CR sequences of the 3R DNA-A fragment were 79, 95, and 77% identical to those of 5L, 3M, and 2U clones, respectively, suggesting that this is a different geminivirus. These sequences were 75 to 87, 82 to 88, and 73 to 81% identical, respectively, to sequences of homologous regions of other tomato geminiviruses, including tomato golden mosaic from Brazil, tomato mottle from Florida, and tomato leaf crumple from Mexico. The bipartite nature of the geminiviruses that were present in the 5L, 3M, 3R, and 2U samples was suggested by the amplification of a DNA-B fragment with degenerate DNA-B primers (PBL1v2040 and PCRc1) (4). These results suggest at least two distinct bipartite Western Hemisphere whitefly-transmitted geminiviruses are associated with tomato virus diseases in Venezuela, and that one of these (sample 3R) may be an undescribed geminivirus. The sequence of the DNA-A fragment from the weed sample was not closely related to the tomato-infecting geminiviruses and, therefore, this weed was not an alternate host of these viruses. Furthermore, because PYMV has been shown to infect tomatoes and cause yellow mosaic symptoms (1), it would be of interest to determine the relationship of PYMV and tomato yellow mosaic geminivirus (ToYMV), which has been reported infecting tomatoes in Venezuela (2), but has not been characterized on the molecular level. References: (1) A. K. Buragohain et al. J. Gen. Virol. 75:2857, 1994. (2) R. C. de Uzcátegui and R. Lastra. Phytopathology 68:985, 1978. (3) M. K. Nakhla et al. Phy-topathol. Mediterr. 32:163, 1993. (4) M. R. Rojas et al. Plant Dis. 77:340, 1993.

Tomato tolerance and purple nutsedge control with sulfuryl fluoride mixes

2021 ◽  
pp. 1-22
Author(s):  
Jialin Yu ◽  
Joshua H. Freeman ◽  
Nathan S. Boyd
Keyword(s):  
Wood Products ◽  
Building Structures ◽  
Tomato Production ◽  
Tomato Plants ◽  
Purple Nutsedge ◽  
Sulfuryl Fluoride ◽  
Stunted Growth ◽  
Tomato Yield ◽  
Industry Standards ◽  
Drywood Termites

Abstract Sulfuryl fluoride (SF) is currently utilized as a fumigant for control of drywood termites and insects in building structures, vehicles, wood products, post-harvest commodities, and food processing facilities. This research investigated the feasibility of using SF as a preplant soil fumigant for Purple nutsedge control in plastic-mulched tomato production. SF treatments included SF injected through drip tapes or SF injected through drip tapes a few hours following shank injection of chloropicrin (Pic). Results revealed that SF alone at 224, 336, or 448 kg ha−1 was generally less effective compared to when it was applied in conjunction with Pic at 168 kg ha−1. SF alone provided inconsistent control of purple nutsedge. In contrast, SF plus chloropicrin (Pic) (SF + Pic) was as efficacious or more efficacious on purple nutsedge than the industry standards including 1,3-dichloropropene (1,3-D) plus Pic (1,3-D + Pic) and metam potassium. None of the fumigant treatments visually injured tomato plants, stunted growth, or adversely affected tomato yield. In one of the four tomato seasons, tomato plants growing in plots fumigated with SF + Pic resulted in taller tomato plants and higher markable yields. Results indicate that soil fumigation with SF + Pic is safe on plastic-mulched tomato and effectively controls purple nutsedge.

scholarly journals Molecular Characterization and Detection of a Genetically Distinct Tomato Chlorosis Virus Strain in Taiwan

Plant Disease ◽  
2018 ◽  
Vol 102 (3) ◽  
pp. 600-607 ◽  
Author(s):  
Ya-Chi Kang ◽  
Yun-Chi Wang ◽  
Chun-Ming Hsia ◽  
Wen-Shi Tsai ◽  
Li-Hsin Huang ◽  
...  
Keyword(s):  
Genomic Sequence ◽  
Phylogenetic Analyses ◽  
Whole Genome Sequence ◽  
Rt Pcr ◽  
Degenerate Primers ◽  
Tomato Production ◽  
Tomato Plants ◽  
Infected Tomato ◽  
Tomato Chlorosis Virus ◽  
Central Taiwan

The whitefly-transmitted tomato chlorosis virus (ToCV) belonging to the genus Crinivirus (family Closteroviridae) affects tomato production worldwide. ToCV was first recorded in Taiwan in 1998 affecting tomato production. In this study, a local virus isolate XS was obtained, after serial whitefly transmissions from a diseased tomato plant displaying general chlorosis were collected in central Taiwan. The whole genome sequence of XS was determined from cDNA fragments amplified by reverse transcription (RT)-PCR, first using the degenerate primers for viruses of Closteroviridae and followed by degenerate and specific primers designed on available sequences of the ToCV isolates. The nucleotide (nt) sequences of RNA-1 and RNA-2 of the XS shared low identities of 77.8 to 78% and 78 to 78.1%, respectively, with genome segments of other ToCV isolates. Nevertheless, the viral RNA-dependent RNA polymerase (RdRp), heat shock protein 70 homolog (Hsp70h), and major capsid protein (CP) shared 88.3 to 96.2% amino acid (aa) identities with other ToCV isolates, indicating that XS is a new strain of this virus. Phylogenetic analyses of these three proteins indicated that all ToCV isolates from different counties outside Taiwan are closely related and clustered in the same clade, whereas the XS isolate is distinct and forms a unique branch. A one tube RT-PCR assay using primers designed from the genomic sequence of the XS was able to detect the ToCV-XS in infected tomato plants and in individual whiteflies. A field survey during 2013 to 2016 revealed a high ToCV-XS prevalence of 60.5% in 172 tested tomato samples, demonstrating that ToCV-XS is becoming an emerging threat for tomato production in Taiwan.

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